Gold medallists Katherine Copeland and Sophie Hosking of Britain celebrate during the award ceremony for the women's lightweight double sculls final during the London 2012 Olympic Games

Gold medallists Katherine Copeland (L) and Sophie Hosking of Britain celebrate during the medal ceremony for the women's lightweight double sculls final in the rowing event during the London 2012 Olympic Games at Eton Dorney August 4, 2012. REUTERS/Jim Young (BRITAIN - Tags: SPORT ROWING OLYMPICS)

Jamaica's Yohan Blake takes the lead in his men's 100m round 1 heats at the London 2012 Olympic Games at the Olympic Stadium

Jamaica's Yohan Blake (R) takes the lead in his men's 100m round 1 heats at the London 2012 Olympic Games at the Olympic Stadium August 4, 2012. REUTERS/Pawel Kopczynski (BRITAIN - Tags: OLYMPICS SPORT ATHLETICS)

Britain's Dwain Chambers starts his the men's 100m round 1 heats at the London 2012 Olympic Games at the Olympic Stadium

Britain's Dwain Chambers celebrates after finishing first in his men's 100m round 1 heats at the London 2012 Olympic Games at the Olympic Stadium

Britain's Dwain Chambers celebrates after finishing first in his men's 100m round 1 heats at the London 2012 Olympic Games at the Olympic Stadium August 4, 2012. REUTERS/Dylan Martinez (BRITAIN - Tags: OLYMPICS SPORT ATHLETICS TPX IMAGES OF THE DAY)

Britain's Adam Gemili leads during heat 5 of the round 1 men's 100m heats at the London 2012 Olympic Games at the Olympic Stadium

Britain's Adam Gemili leads during heat 5 of the round 1 men's 100m heats at the London 2012 Olympic Games at the Olympic Stadium August 4, 2012. Gemili finished second in his heat. REUTERS/Kai Pfaffenbach (BRITAIN - Tags: OLYMPICS SPORT ATHLETICS TPX IMAGES OF THE DAY)

Britain's Greg Rutherford competes in the men's long jump final at the London 2012 Olympic Games at the Olympic Stadium

Britain's Greg Rutherford competes in the men's long jump final at the London 2012 Olympic Games at the Olympic Stadium August 4, 2012. REUTERS/Phil Noble (BRITAIN - Tags: SPORT ATHLETICS OLYMPICS)

Britain's Mo Farah reacts after winning the men's 10,000m final at the London 2012 Olympic Games

Britain's Mo Farah reacts after winning the men's 10,000m final at the London 2012 Olympic Games at the Olympic Stadium August 4, 2012. REUTERS/Kai Pfaffenbach (BRITAIN - Tags: OLYMPICS SPORT ATHLETICS)

Michael Phelps of the U.S. holds up his trophy awarded to him by FINA honouring him as the most decorated Olympian of all time during the London 2012 Olympic Games at the Aquatics Centre

Michael Phelps of the U.S. holds up his trophy awarded to him by FINA honouring him as the most decorated Olympian of all time, after winning the men's 4x100m medley relay final during the London 2012 Olympic Games at the Aquatics Centre August 4, 2012. Phelps ended his incredible Olympic career on the perfect note on Saturday, winning his 18th gold medal for the United States in the men's medley relay, the last time he will swim a competitive race. The trophy reads, "To Michael Phelps, the greatest Olympic athlete of all time, from FINA". REUTERS/Jorge Silva (BRITAIN - Tags: SPORT SWIMMING OLYMPICS)

Gold medallists Rasmussen and Quist of Denmark celebrate next to silver medallists Purchase and Hunter of Britain after competing in the men's lightweight double sculls final during the London 2012 Olympic Games at Eton Dorney

Gold medallists Mads Rasmussen and Rasmus Quist of Denmark (R) celebrate next to silver medallists Zac Purchase and Mark Hunter of Britain after competing in the men's lightweight double sculls final during the London 2012 Olympic Games at Eton Dorney August 4, 2012. REUTERS/Jim Young (BRITAIN - Tags: OLYMPICS SPORT ROWING)

Britain's Greg Rutherford reacts after winning the gold in the men's long jump final at the London 2012 Olympic Games

Britain's Greg Rutherford reacts after winning the gold in the men's long jump final at the London 2012 Olympic Games at the Olympic Stadium August 4, 2012. REUTERS/Phil Noble (BRITAIN - Tags: OLYMPICS SPORT ATHLETICS TPX IMAGES OF THE DAY)